Method for Ultra High Purity Gold

[HAuCl4]

Is there some type of additive, like corn starch or egg white or something, that will help cleaning the AgCl faster than waiting for days to settle completely, before dropping the gold?. :?:

:shock:
I'm not eating an omlette at your house

I met a winemaker that told me he uses egg white to clear fine sediments and turbidity in his wine...so I inmediately thought about silver chloride... Call me nuts!.

 

[BGT]

Hello. I was ending up with the material in the filter after pouring it in there from the Oxalic/BDG Drop. In order to get it all out of the beaker, and be able to re-use the BDG, pouring it all in a buchner funnel with a filter(s) was how I got it out of the beaker.

Is there another way to get it all out of the beaker? (and still keep the BDG)

Thanks.

Mark

 

[lasereyes]

If I remember correctly, they used minute quantities of gold of this purity in the experiments at the Brookhaven national laboratory with the relativistic heavy ion collider. I got to take a look around the place a couple of years ago. They are defiantly on the bleeding edge of experimental physics. Here is a picture of gold ions colliding at extreme temperatures:

 

[jpnuke33]

totaly new to the refining process, and want to learn HOW TO; refine my,
rings to their purest state. easiest way, refining 101 if you will

Thank You,jpnuke33

 

[jimdoc]

totaly new to the refining process, and want to learn HOW TO; refine my,
rings to their purest state. easiest way, refining 101 if you will

Thank You,jpnuke33

Just start reading. You found the right place.
Now you need to do some homework.

Jim

 

[Harold_V]

totaly new to the refining process, and want to learn HOW TO; refine my,
rings to their purest state. easiest way, refining 101 if you will

Thank You,jpnuke33

Yes, I understand.

Here, refining 101 begins with you reading Hoke.

Harold

 

[Militoy]

Is there some type of additive, like corn starch or egg white or something, that will help cleaning the AgCl faster than waiting for days to settle completely, before dropping the gold?. :?:

:shock:
I'm not eating an omlette at your house

I met a winemaker that told me he uses egg white to clear fine sediments and turbidity in his wine...so I inmediately thought about silver chloride... Call me nuts!.

One of my "side interests" is winemaking - though since I moved to the High Desert many years ago, I have pretty much switched over from grapes to local fruits like prickley pears - or to blends of local fruits with grapes. The use of albumen from egg whites to clear turbidity caused by tannin in wine "must" is a time-honored method. Works like a charm.

 

[Lou]

Too bad in the hyper acidic and often oxidizing solutions we use, the albumin would at the least denature (uncoil) and more probably just hydrolyze the peptide/amide bond.

They make flocculants for getting troublesome fine precipitates out of solution.

 

[HAuCl4]

Found a cheap and expedite way to "hydrolyze the crap out" instead. To be released in the Kitchen Warrior pamphlet when it is finished... :lol:
I suspect Republic does something similar for their 5N in one pass process.

I doubt there is anything "new", but anyways... :shock:

 

[Python]

Hi Lou.

Im sorry to bother, but im from south africa and dont know anyone who can help me.
Im new in the refining process, but i dissolved some gold in AR, and want to precipitate it, using Ferrous Sulphate, but nothing happens. can you please help.

Thank you for your time.

 

[Harold_V]

Hi Lou.

Im sorry to bother, but im from south africa and dont know anyone who can help me.
Im new in the refining process, but i dissolved some gold in AR, and want to precipitate it, using Ferrous Sulphate, but nothing happens. can you please help.

Thank you for your time.

We have a policy against double posting. Readers tend to read all posts, regardless of where they are posted on the board---so duplicating can lead to confusion, plus it wastes time of those of us that moderate. It also makes it difficult to find information, due to responses having the potential to be in more than one place.

I have already responded to your inquiry on another thread. Please go there to read what I have to say.

Harold

 

[vichem]

millipore water is full of surfactants, I make my pure water by dubble distilation thru KMnO3 in basic conditions and K2Cr2O7 in acidic conditions, then i have 18,2Mohm

 

[Lou]

You mean KMnO4. Thanks for the thread clutter.

 

[gold4mike]

Resurrecting an old thread...

LazerSteve mentioned earlier in this thread, on 1/24/11, that he was working on a process with a selective gold stripper but would wait to post further about in until he had more data.

Steve, did you ever get the process to where you wanted it? If so, can you share that with us? It seems like I'm doing more and more pins and other plated objects lately and I it would be great to see a better process than the two I'm currently using - poorman's nitric and acid peroxide.

Thanks!

 

[lazersteve]

The experimental method is a back burner project and I have not gotten around to testing it. I did manage to make my reagents for the reaction several months ago, but that is where it stands right now.

Steve

 

[10wt_Percent]

Perhaps Zone Refining as employed in the semiconductor industry is of utility in achieving super-high purity numbers. Just thinkin "outside the flask". :idea:

 

[butcher]

I believe Lou has done something similar to zone refining in a tube furnace, which sounds lab equipment extensive, and complicated to me (the uneducated in that process).

I know nothing about the process, but I assume the gold, or other metals would have to be in a fairly pure state to begin with, just a uneducated guess.

He has discussed that process on the forum.

 

[Lou]

That is gas phase crystal growth from already pure (5N+ material) to get material that is about as pure as it could get to limits of detection on glow discharge mass spectrometry. The process given here has a bad yield, but will give the purest gold in quantity (6N) and the rest of the gold can be recovered and sold. I do not advocate re-using that gold over and over, for the buildup of impurities. Even making 5N gold is difficult--most refiners struggle to achieve that consistently without solvent extraction and/or oxalic acid.

Zone refining can also be done on pretty much any metal. It works better if the metal is less conductive of heat (so gold and silver are very hard to do). One can use a small, high power density coil for the lower melting point metals (i.e. Pt/Ti and below); higher temperatures and it is much more efficient to use a focused electron beam. Zone refining is done in passes wherein a rod of the feedstock material moves through a hot zone that melts. Essentially, the metal recrystallizes and pushes the impurities to the edge of the molten zone. Done many times over, very high purity materials can be achieved. This is often used on silicon crystals that are first grown as boules and pulled with a oriented seed crystal--they are then zone refined for additional purity. Zone refining sometimes is very cost effective for PGM refining when the material is contaminated with elements that are a drag to remove hydrometallurgically and have the appropriate partition coefficient.

One can always recognize zone refined bars by their appearance:

For additional reading:

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=54&t=8910

I'm going to try and be more involved in the ASTM subcommittee for precious metals products and standards, so it'll be interesting to look at application/industry-specific standards development.

Lou

 

[solar_plasma]

Since there has been asked for how to purify up to 999,999, I would like to make everyone who hasn't seen it yet aware of this thread.

 

[jimdoc]

I have some Alfa Aesar Premion 99.9975+% gold.
https://www.alfa.com/en/catalog/11390

They don't list 99.9999 gold.